-LRB- CNN -RRB- -- Renee Mosier was one of an estimated half-million patients in the United States who were unable to get the drugs they needed because of shortages .

`` You feel like you 're in a fight with one hand tied behind your back , '' said Mosier , 56 .

It was a fight she lost in June .

According to the Food and Drug Administration , the number of drug shortages has increased nearly 300 % since 2005 . More than half of the drugs on the shortage list are considered critical -- meaning they have no alternative . The drugs most often in short supply include anesthetics and oncological drugs .

Mosier was diagnosed in 2006 with ovarian cancer , the fifth-deadliest cancer for women , according to the American Cancer Society .

Surgery and treatment were able to keep her tumors at bay until 2009 , when she returned to surgery . She was back in remission until June 2011 , when her cancer appeared once again .

Mosier was able to get her required surgery , but her doctor , Dr. Wendel Naumann , was unable to get Doxil , the chemotherapy treatment she needed .

' A huge , growing crisis in this country '

`` This is a huge , growing crisis in this country , where we 're actually having to ration drugs , '' said Naumann , who calls it `` unbelievable . ''

In November 2011 , Mosier appeared on CNN 's `` Sanjay Gupta , MD '' to share her ordeal . She told Dr. Sanjay Gupta , CNN 's chief medical correspondent , that without Doxil , she had few alternatives .

`` At the time we just said , ` Let 's go with what we have , and see what happens , ' and the cancer pretty rapidly recurred . ''

Mosier was never able to get another dose of Doxil and spent the last month of her life in hospice care . She was able to make one last trip -- to the Bahamas to attend her daughter 's wedding .

In a follow-up interview with Mosier 's daughters on this past weekend 's `` Sanjay Gupta , MD , '' daughter Michelle Philipp told Gupta , `` We were n't sure until even -LRB- the -RRB- last minute if she was able to come . So we bought her the ticket , hoping it would give her something for her to look forward to , and she did , and it was just wonderful . ''

On June 29 , 2012 , Mosier died .

Philipp 's sister , Nicole Penninger , did n't hide her frustration with the situation . `` You feel like you 're in this time now , it 's 2012 . You feel like , you 're in America . Why ca n't she get these drugs , that she needs to treat something so serious ? ''

Critical dependence on a few companies

How did it get to this point ?

According to Naumann , `` We only have a couple of companies , and the problem is that if one of these companies goes down because of FDA inspections , manufacturing problems or something like that , we do n't have those drugs if only one company is making them . ''

The House Oversight Committee came to the same conclusion . In a recent report , the panel claimed the FDA -- the very agency tasked with dealing with shortages -- is partly to blame for the shortage situation .

The report paints a scathing picture of a regulatory agency that gave little consideration to the potential outcome of its actions .

`` The committee has learned that FDA regulatory activity has effectively shut down 30 % of the total manufacturing capacity at four of America 's largest producers of generic injectable medications , '' it said .

`` The FDA has failed to ensure that enforcement and compliance activities are conducted in a manner that does not create unnecessary shortages of critical drugs , '' according to the House report .

That report is disputed by the FDA .

`` Let me just say , very clearly , that the report is incorrect , '' Dr. Sandra Kweder of the FDA said on `` Sanjay Gupta , MD. '' `` We are not in this situation because the FDA is shutting down companies . FDA is part of the solution . ''

Kweder is the deputy director of the FDA 's Center for Drug Evaluation and Research , Office of New Drugs .

She said FDA inspection processes and enforcement rules have not changed .

`` What has changed is that there is an aging manufacturing infrastructure , and there are serious quality problems that have required companies to close down to fix the problems . ''

On Monday , the FDA issued a letter to Rep. Elijah Cummings -LRB- D-Maryland -RRB- of the House Oversight Committee , responding to the committee 's blaming the FDA for the shortages . The letter reiterated the report was false and emphasized the FDA is part of the solution .

What happened with Doxil

While Doxil is not a generic drug , it was manufactured by Ben Venue Laboratories , one of the country 's four largest producers of generic injectables .

The Ben Venue lab was the sole manufacturer of Doxil in the nation . It voluntarily shut down in November 2011 .

A May 2011 FDA inspection found a string of problems , including inadequate oversight and metallic particle shards in some of the drugs produced on site .

A November 2011 FDA inspection found additional problems , including finding a 10-gallon can in a storage area that contained urine .

In a statement sent to CNN after it shut down , Ben Venue labs said its team `` has been working around the clock to implement changes needed to ensure a more sustained supply of the medicines we produce and to address the manufacturing-related issues at our facility noted in recent inspections by the FDA and other global regulatory agencies . ''

However , Ben Venue maintained that none of the Doxil supply was affected .

From their findings , the House Oversight Committee found that 58 % of the drugs on the shortage list were produced at facilities cited by the FDA . They also found that the FDA 's warning letters increased 156 % from 2010 to 2011 .

Dr. Scott Gottlieb , former FDA deputy commissioner , said the FDA is n't concerned about the outcome , though .

`` They go in , they inspect facilities and then they issue findings . You 're not asked to worry if there 's a stable supply . You 're asked to make sure the facility falls in line . ''

But Kweder says it 's quite the opposite . `` Well , it 's our job to worry about it in our drug shortages team . When we issue warning letters today , we ask companies to very specifically communicate with us how they plan to address the problem , so we can assess what the potential of a shortage is , '' she told CNN .

Kweder also cited the recent reauthorization of the Prescription Drug User Fee Act as a key to preventing shortages .

Signed by President Barack Obama earlier this month , the act will help the FDA expedite the drug review process , particularly for drugs in shortage . It will also require companies to notify the FDA if they anticipate an interruption in production .

`` It allows us as a regulatory agency to step in , and try and prevent the shortage in the first place , '' Kweder said . `` So for example , we can go to other companies to ask them to increase their production . We can assist companies that are having difficulties to finding alternatives for the difficulties they are having , and even in rare cases , we can seek sources of medications from other countries , where they might be being produced to our standards . ''

Help comes from abroad

That 's actually what happened in the case of Doxil .

In February , the FDA stepped in and allowed the importation of Lipodox from an Indian manufacturer , a possible therapeutic alternative . But Naumann said he was never able to get his hands on it .

`` The key is having enough notice , '' says Kweder . Since Obama signed an executive order requesting early notification from manufacturers in November 2011 , more and more companies have been able to give the FDA the needed heads-up .

`` We 've done that successfully innumerable times . Just since January , at our count , we 've prevented 94 to 100 shortages , things the public never sees , '' Kweder told Gupta .

`` I think it 's a start , '' says Naumann , but it 's not enough .

`` I think these shortages are going to continue because of the same problems that we have . There are certainly fixes out there for it . I do n't think these shortages are going to go away because of this bill . ''

For Mosier 's daughters , it 's all too late .

Had Mosier gotten the Doxil , Philipp says , `` I think she thought it would have at least put her in remission in another time , or it would save her from the chemo that was detrimental to her . ''

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Renee Mosier , who had cancer , died after not receiving the drug she needed

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The number of drug shortages is up 300 % since 2005 , according to the FDA

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The House Oversight Committee blames the FDA for shortages